Anti-suffocation valve



Jan. 9, 1968 C. M. 4BLACKBURN ETAL ANTI-SUFFOCATION VALVE Filed Aug. ll,1965 man n www N Y NG n r. E A 0. N VMM J m@ AWA MSV.. $0 R RH P HR a nm mw vm mw E d r .n Jw/ hv um um mm Q 2l mm n. vm .5.. mm *I 1 mm l. ENol om .mwll ||||w| E K g 2, mw \V\` n \N il. w .3. bv Q V mm Vi m uw 7/mr mw G mm ,I Km mw mm No mw United States Patent O 3,362,420 ANTI-SUFFCATION VALVE Charles M. Blackburn and Richard S. Brasllears, SilverSpring, Md., assignors to the United States of America as represented bythe Secretary of the Navy Filed Aug. 11, 1965, Ser. No. 479,021 Claims.(Cl. 137-81) ABSTRACT OF THE DISCLOSURE There is disclosed a safetyvalve for automatically venting an oxygen mask to the atmosphere in theevent that the oxygen supply becomes depleted while the wearer isunconscious and further provides that the valve will not automaticallyvent to the atmosphere if the wearer is above a predetermined altitudeor submerged in water.

The present invention relates to an anti-suffocation valve and, moreparticularly, to a valve for an oxygen mask which prevents suffocationwhen the wearer is unconscious.

It is the continuous desire of developers of oxygen masks, flighthelmets, and other similar life supporting equipment to make them saferfor those who use them. However, the equipment that is available todaydoes not have a safety feature that enables the artificial respirationsystem to be vented automatically to the atmosphere in the event thatthe system becomes depleted of oxygen when the wearer is unconscious.Such a safety feature would be desirable in the event that the oxygensupply was depleted yet the wearers altitude was such that adequaterespiration could be maintained by the ambient at- Inosphere. Of course,if the wearer is conscious, he would merely remove the mask or helmet.The problem arises, however, when the wearer is unable to do so, forexample, when he is unconscious. It is, therefore, desirable to providea device for automatically venting the respiration system to theatmosphere when the oxygen supply falls below a predetermined level. Ofcourse, if the ambient atmosphere is not capable of supporting adequaterespiration, the system should not be vented thereto. This would occur,for example, when the wearer is either above a predetermined altitude ormomentarily submerged in water.

It is, therefore, an object of the present invention to provide ananti-suffocation valve for automatically venting an artificialrespiration system to atmosphere should it become depleted of oxygen.

Another object is to provide an automatically venting valve which isprevented from venting to the atmosphere when in use above apredetermined altitude.

Still another object of the present invention is to provide a valvewhich is prevented from venting to the atmosphere when submerged inwater.

A further object of the invention is the provision of an automaticallyventing valve which is characterized by simplicity of construction,reliability, low cost and ease of installation.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings in which:

FIG. l is a side elevation view, partly in section, of a preferredembodiment of the invention;

FIG. 2 is a side elevation view of a breathing mask incorporating theinstant invention; and

FIG. 3 is a schematic View, partially in elevation, of a portion of theinvention.

Referring now to the drawings wherein like reference charactersdesignate like or corresponding parts throughout the several views,there is shown in FIG. 1 a generally cylindrical housing 5 having alongitudinally flattened portion 6 and a flange 7 to facilitate mountingthe housing 5 to the interior of a breathing mask or helmet 8 used in anartificial respiration system. The housing 5 is provided with a chamber9 which is closed at one end by an integral end wall 11. At its oppositeend, the housing -5 is threaded internally to receive a solenoidmounting plate 13 having a solenoid 15 attached thereto as by a screw17.

A valve element 19, mounted in the chamber 9, has an internally threadedbase 20 that threadedly engages a reduced threaded boss 21 extendingaxially from the inner end of the solenoid 15. The valve element 19 hasa tubular central wall 22 extending from the base 20 and terminating inan outwardly directed flange 23. Mounted within an annular groove 24 onthe outer surface of the flange 23 is a sealing ring 25 for sealing theannular space between the valve element 19 and the housing 5. The innerwall of the valve element 19 is flared outwardly toward its inner end todefine a Valve seat 26 while the tubular central wall 22 of the valveelement 19 is provided with a pair of ports 27. The housing 5 is alsoprovidedV with a pair of ports 29 and 31, Iport 29 opening to theambient atmosphere and port 31 opening into the interior of the helmet8. In a manner to be explained, the ports 29 and 31 may be selectivelyplaced in communication with each other to enable the ambient atmosphereto enter the interior of the helmet when the artificial oxygen supplybecomes depleted.

The solenoid 15 actuates a plunger 33 attached by a screw 35 to a discshaped valve member 36 which is movable into engagement with the valveseat 26 lby the movement of the plunger 33. The disc shaped valve member36 includes a toroidal sealing element 37 which abuts the valve seat 26when the valve is closed. A retaining ring 38 is clamped between theinner end wall of the plunger 33 and the sealing element 37, therebysecuring the element 37 against the valve member 36. The valve member 36is urged toward an open position by a spring 39 which is coaxiallymounted around the solenoid plunger 33 and is confined between the innersurface of the Ebase 20 of the valve element 19 and the confronting faceof the sealing element 37.

Abutting the valve member 36 is a bi-chambered bellows 41 disposedbetween the valve member 36 and the end wall 11 of the housing. Thebi-chambered bellows 41 is divided into two adjoining bellows 43 and 4Sby a common wall 46 while each is closed at its outer end by the endwalls 47 and 48, respectively. The outer wall 47 abuts the valve member36 and the bellows 43 is permanently lled with a gas, such as nitrogen,to form a pressure cha-mber. The outer wall 48 of the smaller bellows 45is connected to a mounting plate 49 which is secured to the end Wall 11by screw rneans 54. A tubular spacer 50 is attached to the inner surfaceof the outer wall 48, and extends axially through the bellows 45 towardsthe common wall 4-6.

A port 51 extends through the outer wall 48 and the mounting plate 4'9to vent the spacer 5) and the interior of the bellows 45 to thepassageway 53 in the end wall 11. A ring gasket S5 is contained in anannular groove 56 on the mounting plate `49 to seal the passageway 51from the chamber 9. A second spacer 518 is axially mounted, as bywelding, to the common wall 46 of the larger bellows 43, which spacerlimits the collapsing motion of the larger bellows 43 by acting as astop against the outer wall 47. In a similar manner, the tubular spacer50 limits the collapsing motion of the smaller bellows 45'.

Referring now to FIG. 2, the interior of the breathing mask 8 issupplied with oxygen from an external so-urce 59 through a pressureregulator 60. The oxygen supply 59 is also directly connected by aline61 to the passageway 53. In operation, the pressure of the -oxygen fromthe source 59 passes through the line 61, the passageway 53, and thetubular spacer 50 to the interior of the bellows 45. This pressureexpands the smaller bellows 45, thereby moving the valve member 36against its valve seat 26. This movement prevents communication betweenthe atmosphere port 29 and the interior port 31 until the pressure ofthe oxygen source drops below a predetermined value, wherein the forceexerted by the smaller bellows 45 is overcome by the spring 39 and thevalve member 36 is opened. However, should the oxygen source becomedepleted when the altitude of the aircraft is such that the ambientatmosphere is insufficient to sustain adequate respiration, the largerbellows 43 would, notwithstanding the drop in oxygen pressure within thebellows 45, maintain the valve member 36 firmly seated against the valveseat 26, thereby preventing venting of the breathing mask 8.

As illustrated in FIGS. 1 and 2, the ambient atmosphere port 29 issurrounded by a pair of annular metallic rings 63 and 64 contained inthe grooves `66 of an annular nonwetting gasket 65'.

As illustrated in FIG. 3, the outer ring 63 is connected in series withan energy source 62, such as a battery, and one of the terminals of thesolenoid while the inner ring 64 is connected to the -other terminal ofthe solenoid 15. If the wearer of the mask 8 should be momentarilysubmerged under water and unconscious when the oxygen supply becomesdepleted, he would be in grave `danger if the port 29 were opened.Therefore, in such a situation, the water will complete the seriescircuit by forming a conductive path between rings 63 and `64, therebydriving the plunger 33 into the solenoid to seat the valve member 36 andprevent water from entering the interior of the valve through ports 29and 31. When the mask is removed from the water, the non-wettingproperties of the gasket 65 will again open the series circuit and allowthe interior of the valve to vent to atmosphere.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. An anti-suffocation valve for use in an artificial respiration systemhaving an oxygen supply comprising:

a tubular housing having a pair of axially spaced ports therein;

a solenoid having a plunger, said solenoid being secured to one end ofsaid housing;

a valve element secured to said solenoid, said Valve element having avalve seat disposed between Said ports;

a valve member secured to said solenoid plunger, said valve memberabutting said valve seat when said solenoid is energized to therebyclose communication between said ports;

a spring concentrically mounted around said solenoid plunger for urgingsaid valve member away from said valve seat;

a bellows having first and second chambers therein, said first chamberbeing secured to the other end of said housing and said second chamberabutting said valve member, said first chamber having an axiallyydisposed tube therein extending throughout a substantial portion of thelength of said chamber, said tube being in communication with apassageway through said housing which is adapted to be pressurized bysaid -oxygen supply, said second chamber having an axially disposed tubetherein and being filled with a gas so as to define a pressure chamber;and

a pair of metallic .rings disposed around one of said ports, said ringsbeing separated by a non-wetting gasket and being electrically connectedto said solenoid for actuation thereof when said rings are submerged inwater;

whereby said Valve member is normally held against said valve seat bythe pressure of the oxygen in the first chamber of said bellows but willseparate when said oxygen is depleted unless the altitude is such thatthe ambient atmosphere will not sustain adequate respiration or therings are submerged in water.

2. An anti-suffocation valve comprising:

a housing having a pair of ports therein;

valve means adapted to open and close communication between said ports;

resilient means urging said valve means towards an open position;

first pressure means in communication with a respirant supply formaintaining said Valve closed when the pressure of said supply is abovea .pre-determined value;

secon-d pressure means for maintaining said valve closed fwhen theambient pressure is below a pre-determined value; and

means for maintaining said valve closed when submerged in Water.

3. An anti-suffocation valve, las set forth in claim 2,

wherein said first and second pressure means comprise:

a bi-chambered bellows, one end of which abuts said valve means and t-heother end of which is secured to the end wall of said housing.

4. An anti-suffocation valve, as set forth in claim 3, wherein saidmeans for maintaining said valve closed when submerged in watercomprises:

a solenoid having a plunger secured to said valve means; and

an electric circuit for operating said solenoid, said circuit includinga normally open switch which is adapted to close when submerged inwater.

5. An anti-suffocation valve, as set forth in claim 4,

wherein said normally open switch comprises:

a pair of metallic rings separated by an annular nonwetting gasket.

6. An anti-suffocation valve comprising:

a housing having a pair of ports therein;

valve means establishing communication between said ports when in :anopen position;

first means in communication with a respirant supply for closing saidvalve when the pressure of said supply is above a predetermined value;and

second means responsive to water for maintaining said valve in a closedposition when submerged in said water irrespective of the pressure ofsaid supply.

7. An anti-suffocation valve, as set forth in claim 6,

comprising:

third means for maintaining said valve in a closed position when theambient atmospheric pressure is below a predetermined value irrespectiveof the pressure of said supply.

8. An anti-s-uffocation valve, as set forth in claim 7,

wherein said first and third means comprises a bi-chambered bellows.

5 6 9. An anti-sniocation valve, as set forth in claim 6, ReferencesCited wherein said second means comprises: UNITED STATES PATENTS asolenoid secured to said valve means; and a pair of metallic elementselectrically connected to 2387123 10/1945 Demmg 12g-*1465 said solenoidfor energizing s-arne when said elements 5 2822816 2/1958 Schutmaat137-80 are submerged in Wan 2,853,268 9/1958 Hu-glles 137-505.22 X 10.An anti-suffocation valve, as set forth in claim 9, 3092104 6/1963Cassldy 12S-142 wherein said elements comprise:

a pair of rings disposed around one of said ports, said WILLIAM F' O DEAPrmary Examme' rings being separated by -a non-wetting annular 10. R.GERARD Assistant Examiner. gasket.

